Crosby, P. B. (1979). Quality is free: The art of making quality certain. McGraw-Hill.
शिकागो शैली (17वां संस्करण) प्रशस्ति पत्रCrosby, Philip B. Quality Is Free: The Art of Making Quality Certain. New York: McGraw-Hill, 1979.
एमएलए (9वां संस्करण) प्रशस्ति पत्रCrosby, Philip B. Quality Is Free: The Art of Making Quality Certain. McGraw-Hill, 1979.
चेतावनी: ये उद्धरण हमेशा 100% सटीक नहीं हो सकते हैं.